This section provides background information related to the present disclosure and is not necessarily prior art.
Retaining walls and seawalls are commonly built between adjacent land formations and/or a land formation and a body of water to prevent the erosion or the movement of soil, sand, gravel or other ground material. Such retaining walls maintain an aesthetically pleasing appearance and limit the amount of maintenance required to replace or repair ground material that can move due to the flow of water. Retaining walls are generally vertical rigid structures that retain the soil, sand, gravel or other ground material that is located on one side of the retaining wall from being washed or otherwise eroded away by the water that flows, collects or otherwise moves through the ground material. The term retaining wall as used herein includes various walls and other structures used to prevent the erosion or movement of ground materials as a result of water pressure, water flow or other cause of ground movement. These various retaining walls include seawalls, bridge abutments, bulkheads, spillways and other erosion control barriers. Retaining walls can be composed of materials such as concrete, steel sheet pile, vinyl sheet pile, wood and other materials.
Rain, waves, tidal changes, groundwater flow or other sources of water can be deposited on the ground material on one side of the retaining wall over time. The accumulation of water on one side of the retaining wall creates hydrostatic water pressure against the back side of the retaining wall. Unless the hydrostatic water pressure is relieved, the retaining wall can be damaged or otherwise fail.
One way of relieving the hydrostatic water pressure that may exist on the retaining wall is to add drain holes (also known as weep holes) through the retaining wall. While the drain holes can be effective for relieving the hydrostatic water pressure, the drain holes have disadvantages. First, the drain holes can become clogged which prevents the drain holes from relieving the hydrostatic water pressure. Second, the drain holes can permit soil or other ground material to pass through the drain hole. The loss of ground material through the drain hole can cause sinkholes or other problems to develop. Filter assemblies can be inserted into the drain holes to permit water to pass through the drain hole while preventing ground material from being displaced.
Another way of limiting the hydrostatic water pressure that can build on one side of a retaining wall is to bury, bore, insert or otherwise include drain tubes or drain pipes in the ground material. Such drain tubes can extend away from the retaining walls and through the ground material. The drain tubes can be perforated or otherwise connected to water collectors in order to collect water that is deposited in or on the ground material and to move the collected water toward the retaining wall and through the retaining wall through the drain holes. It can be difficult to align the drain tubes relative to the retaining wall and relative to the drain holes. Such alignment problems can result in difficulties in connecting filter assemblies to both the retaining wall and to the drain tube to allow hydrostatic water pressure to be relieved from both the ground material adjacent to the filter assembly and from the water collected by the drain tube.
Repairing failed drain holes, repairing failed drain tubes or repairing land formations that are supported by retaining walls requires costly excavation that takes considerable time and effort to complete. There exists a need, therefore, for improved filter assemblies that address the foregoing issues while still providing hydrostatic water pressure relief and erosion control.